The use of UPS's having battery back-up systems to provide regulated, uninterrupted power for critical and/or sensitive loads, such as computer systems, and other data processing systems is well known. In one application, one to several UPS's can be connected to a computer network so that the network can communicate with each UPS to allow remote monitoring and control of the UPS's.
In some instances, it may be necessary or desirable to know how long a network connected UPS was inoperative or operating on a battery. Prior methods of detecting the downtime of a UPS included manually searching through trap logs to look for a critical state change of a UPS and making an estimate of the amount of time the UPS was down. However, the methods can be ineffective and time consuming if hundreds or thousands of UPS's are connected to a computer network.
One device, PowerNet, manufactured by the American Power Conversion of W. Kingston, R.I., provides to a user on a computer network a notice of a UPS failure. However, PowerNet doesn't provide a user with a notice of the failure's duration.